This ELISA kit provides quantitative measurement of CD81 (TAPA-1) in human serum, plasma, cell lysates, and tissue homogenates, supporting immunological research into this tetraspanin's roles in immune cell signaling and viral entry. Because CD81 is predominantly membrane-bound and shed at low levels into circulation, accurate quantification demands both high sensitivity and compatibility across soluble and cell-associated sample formats.
Detection Range: The 23.5–1500 pg/mL range accommodates the low picogram-level concentrations of soluble CD81 typically found in human plasma while also capturing elevated levels observed in hepatic inflammation and chronic HCV infection, minimizing the need for extensive sample concentration or dilution.
Sensitivity: At 11.75 pg/mL, the kit detects soluble CD81 in samples where shedding is minimal, such as healthy donor serum or conditioned media from unstimulated B cells, where circulating levels can fall below 50 pg/mL.
Sample Compatibility: Validation across plasma, serum, cell lysates, and tissue homogenates enables researchers to correlate circulating soluble CD81 with membrane-bound expression in lymphocytes or hepatic tissue within a single experimental framework.
Assay Efficiency: The 1–5 hour protocol requiring only 50–100 µL accommodates limited clinical specimens and primary cell lysates, supporting studies where patient biopsy material or sorted immune cell populations restrict available sample volume.
This kit is directly applicable to studies of hepatitis C virus entry mechanisms, B-cell co-receptor complex function, and exosome-mediated intercellular communication.